Technical issues with Heroes III.

I'm a bit slow, and I couldn't find anything by searching the forum, and Google didn't give me any useful results. The problem: when I launch the game, it crashes with a message saying that there isn't enough disk space. Of course, there's plenty of space. I've tried changing the free space on the disk, uninstalling and reinstalling the game, and restarting my computer, but the error persists. Question: is it possible to fix this without reinstalling the game? Everything was working fine until today. It's the unpatched version, straight from the disc. P.S. - When registering, the month and date of birth fields seem to be set up for a female name, as March is treated as a feminine noun. Thanks in advance for your help.